Directing Web users to relevant Web content can generate significant revenue for those content providers. For example, if a user is looking for information about purchasing an automobile, then an automobile dealership owning a website has an improved chance of making a sale or at least marketing to an apparently interested consumer if the user navigates or is directed to the dealership's website. As such, website owners are willing to pay for increasing traffic to their websites, especially when the increased traffic is concentrated with users particularly interested in the products and services their businesses offer.
To this end, website owners, and those who direct Web users to such websites, are challenged to distinguish which users are interested in which websites. In some existing approaches, banner ads may be associated with Web pages of similar subject matter (e.g., Ford may advertise on a Web page containing an article about automobile safety), banner ads may be served up based on cookie information on the user's system, and sponsored links may be shown on search engine results pages based on the search keywords entered by the user. Nevertheless, many other opportunities to capture relevant user interest are missed because it remains difficult to discern a user's navigation intentions from the information available during a browsing session.